title: Tunable liquid crystal q-plates with arbitrary topological charge.
abstract: Using a photoalignment technique with a sulphonic azo-dye as the surfactant aligning material, we fabricated electrically tunable liquid crystal q-plates with topological charge 0.5, 1.5 and 3 for generating optical vortex beams with definite orbital angular momentum (OAM) 1,3 and 6 per photon (in units of ¯h), respectively. We carried out several tests on our q-plates, including OAM tomography, finding excellent performances. These devices can have useful applications in general and quantum optics.
authors.affiliation: Dipartimento di Scienze Fisiche, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Napoli, Italy. sergei.slussarenko@na.infn.it
authors.forename: Sergei
authors.initials: S
authors.lastname: Slussarenko
authors.forename: Anatoli
authors.initials: A
authors.lastname: Murauski
authors.forename: Tao
authors.initials: T
authors.lastname: Du
authors.forename: Vladimir
authors.initials: V
authors.lastname: Chigrinov
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Marrucci
authors.forename: Enrico
authors.initials: E
authors.lastname: Santamato
mesh_terms: D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D050866:Liquid Crystals / Q000737:chemistry* / Q000528:radiation effects*; D008422:Materials Testing; D012031:Refractometry / Q000295:instrumentation*; D012542:Scattering, Radiation